Switching mechanism for double-filament electric lamps.



No. 740,369. PATENTED sum-29, 1- 03. MoGULLOUGH. I SWITCHING MECHANISM FOR DOUBLE PILAMENTELEGTRIO LAMPS.

APPLIGATION FILED DEC. 10, 1902.

H0 HODBL.

mowbo Patented Septemk er 29, 1903.

PATENT OFFICE.

JOHN MOCULLOUGH, OF NEWARK, NEW JERSEY.

SWITCHING MECHANISM FOR DOUBLE-FILAMENT liLECTRlC LAMPS.

SPECIFICATION forming part of Letters Patent No. 740,369, dated September 29, 1903. Application filed December 10,1902. Serial No. 134,618. (No model.)

of New Jersey, have invented certain new and useful Improvements in Switching Mechanisms for Double-Filament Electric Lamps, of which the following is a specification.

My invention has for its object to provide switching mechanisms actuated by a partial rotation of the lamp for controlling the circuit connections of a two-filament electric lamp in which the connections with the leads are made through plates carried on the butt of the lamp and contacting when the lamp is locked in its socket with contact-posts on the latter, the locking of the lamp within its socket being eifected by a bayonet-joint on a partial rotation of the lamp therein. Such sockets and single-filament lamps therefor are in common use. As an example thereof I refer to what is generally known as the Swan-Edison, and I will hereinafter describe my invention as applied to such fixtures, although it will be understood that it may be applied to analogous constructions.

With this object in view my invention consists in means which, specifically considered, consist of a pin pivoted onone of the interlocking parts and adapted to engage a bayonet-slot in the other, whereby a bayonet-joint with a range of movement over that required for the interlocking of the lamp and socket ,is provided and properly-disposed contactpoints and electrical circuits whereby such excess of movements of the twoparts may be utilized for effecting changes in the circuits of the lamp; and it further consists in the construction, arrangement, and combination of the several parts of which it is composed, as will be hereinafter more fully described and claimed.

Referring to the accompanying drawings, in which corresponding parts are designated by corresponding marks of reference, Figure 1 is a perspective view of a lamp having my invention applied thereto. Fig. 2 is a side elevation of a lamp similarto that shown in Fig. I. mounted in its socket, parts being broken away for the purpose of better illustration. Fig. 3 is a plan view of the butt of the lamp with one form of circuit connections diagrammatically illustrated. Fig. 4 is a vertical central section on line t 4 of Fig. 5 through the butt of a lamp having my invention applied thereto. Fig. 5 is a horizontal section on line 5 5 of Fig. 4:.

The socket a shown by me has located in its closed end, on opposite sides of its center, two spring-pressed contact-posts b and 0, connected, respectively, with the conductors d and e, and has cut in the skirt f thereof, on each of two diagrammatically opposite sides, a bent slot g, provided with a holding-lug it. As this socket by itself forms no part of my invention, being that known as Swan-Edison, no further description thereof is necessary.

The lamp 11 has two filaments kand ltherein and has upon its base the collar m, the butt of which is closed by a disk n, of insulating fiber, upon theouter surface of which are mounted three contact'plates 0, p, and q, of which 0 is a semicircle and pand g are quadrants.

In two diametrically opposite sides of the base of the collar or I form arc-shaped slots 7", through which projects the locking -pin .9, which plays between substantially radial shoulders t, formed on the under surface 'of the disk m, the ends of the pin being adapted to be inserted in the bent slots g of the'socket and to thus hold the lamp therein, the conbeing so disposed in tact-plates o, p, and q the socket that the post 22 will then be in contact with the plate 0 and the post 0 in contact with the plates 10 or q, depending upon the position of the pin 3 in the slots r. With a position of the lamp in the base that moves the pin to one extreme of its path, as defined by the slots 7', the post 0 and the plate 1) con tact, while with the opposite movement of the lamp the post 0 and plate q contact. The

are shape given the slots r causes the springpressed posts I) and e to tend to hold the pin at one or the other of its limits of movement, as in passing from the one to the other the pin must ride over the raised centers of the slots, and thus throw the lamp farther into the socket against the pressure of the posts.

It will be seen that the lamp may be readily removed from the socket by disengaging the pin 3 from the slot g in the latter and can as readily be relocked in place by reinserting the pin in the open end of the slot gand turning the lamp until the pin is moved thereby to drop in behind the lugsh. This having been accomplished, the lamp, owing to the manner in which the pin is mounted therein, may be rotated to a limited extent without causing a corresponding movement of the pin or unlocking the bayonet-joint securing the parts together, this limited rotation being sufficient to change the contact of the post from plate p to plate q, or vice versa.

In Fig. 3 I have shown one way in which the two filaments 70 and I may be connected up. The filament 7c is shown as having its opposite terminals connected to the plates 0 and q, while the filamentl is shown as connected to the plates 19 and q. Thus when the lamp is turned to cause the posts I) and c to make contact with the plates 0 and q the filament is is in circuit between the wires e and f, while when turned so that the posts make contact with the plates 0 and 19 both filaments k and Z are connected in series between the wires. By properly positioning the filaments the lamp may be caused to yield a smaller quantity of light with the two'filaments in series than with the single filament 7c in circuit, as is well known, and as far as this invention is concerned the filaments may be connected to the plates in any desired manner, as the precise circuit connections accomplished by the rotation of the lamp forms no part thereof.

By means of the shoulders '15 in the disk 72 I in effect pivot the pin .9 at the center of the disk and hold it diametrical to the butt of the lamp at all times. This is of practical importance, as otherwise the pin working .freely in the slots in the collar would be able to assume other positions, in which it would not properly enter the diametrically-disposed slots g in the base. The ends of the pins are reduced in diameter to form shoulders u, which by bearing on the inner surface of the collar prevent the pin falling through the slots 1", and a diaphragm w is placed Within the collar to cover the pin and prevent the plaster used for sealing the butt of the bulb from interfering with the movement thereof.

Having thus described my inventiotnwhat claim as new, and desire to secure by Letters Patent, is

1. In a switching mechanism for a two-filament electric lamp, the combination with a lamp-socket therefor, one of the said parts having slots therein, and the other having a movable member to engage the said slot, forming a bayonet-joint, whereby the parts may be moved in relation to each other without releasing the bayonet-joint, and contacts, connection between which is made and broken by the relative rotation of the two parts substantially as described.

2. In a switching mechanism for a two-fila ment electric lamp, the combination with a lamp having a plurality of contacts thereon, connected to its filaments, of a pin pivoted on the butt of the lamp, and a socket having bent slots in which the pin engages, and having'contact-posts adapted to contact with the plates upon the lamp, according to the position of the lamp'in the socket, substantially as described.

3. In a two-filament electric lamp the combination with the globe and filaments, of a collar surrounding the base of the lamp, contact-plates upon the base connected with filaments, and a pin projecting beyond the collar and pivoted at the center thereof, substantially as described.

4. In a two-filament electric lamp, the combination with the globe and filaments, of a collar surrounding the base of the lamp and having elongated slots in its opposite sides, a pin projecting through the said slots and movable therein lengthwise of the slots, and contact-plates carried by the collar and connected with thefilaments, substantially as described.

5. In a two-filament electric lamp, the combination with the globe and filaments, of a collar surrounding the base of the lamp, having arc-shaped slots in its opposite sides, a pin projecting through the said slots and movable therein, and contact-plates carried by the collar and connected with the filaments, substantially as described. 6. In a two-filament electric lamp, the combination with the globe and filaments, of a collar surrounding the base of the lamp and having slots in its opposite sides, an insulating-disk closing the end of the collar, having radial shoulders on its inner face, a pin projecting through the said slots and centrally pivoted by the shoulders on the disk and contact-plates on the disk connected with the filaments, substantially as described.

Signed by me at Washington, District of Columbia, this 24th day of November, 1902.

JOHN MCOULLOUGH.

Witnesses:

VERNON M. DQRSEY, STEWART HUNT HARPER.

ICC 

